1. Field of the Invention
The present invention relates to add-on parts for a vehicle body and, more particularly, to a method for installing an add-on part on the vehicle body.
2. Description of the Related Art
In conventional methods for robot-guided automatic installation of add-on parts on vehicle bodies, a vehicle body is initially moved by a conveyor system into a production area, into which the add-on parts are also supplied via storage equipment or containers. Add-on parts include, for example, engine hoods, tailgates, wings or doors. During installation of the add-on part, add-on parts are removed from a respective container by a robot and installed on the vehicle body.
DE 37 26 292 C1 describes a method for installing vehicle doors having a door body forming a load-bearing structure, in the cavity of which a unit carrier fixed to the door body is arranged to hold door internal assemblies. Here, the door body without unit carrier is first inserted with an accurate fit into door openings on the body that are provided for this purpose. After that, the door body that is used is detected by performing measurements at defined measuring points. Measured values determined in the process are related to further measured values that are determined at measuring points on the body in an area of the door pillar and roof frame. The door body is then dismounted and transported to a door installation station. There, the vehicle door is completed by installing the unit carrier and further internal fittings, with the aid of a door installation device using the measured results at the measuring points. Finally, renewed installation of the completed vehicle door is performed on the vehicle further finished in the meantime in parallel operations.
WO 1996/036525 discloses a method for the automatic installation of a component of a motor vehicle body, in which the motor vehicle body is measured automatically before installation of the component. After that, a necessary installation position of the component is determined and an installation device installing the installation part is controlled appropriately. Following the installation of the installation part, an actual position of the component in relation to the motor vehicle body is again measured. Correction data for the installation of the corresponding component of the following motor vehicle body is obtained from the determined position of the installed component.
DE 103 47 554 A1 describes a method for installing a body part on a body, in which an installation device provided with drivable actuators is used. Here, the installation device has a holder for the body part. After the body part has been picked up by the holder, a measuring position of the body part on the body is approached and alignment and gap dimensions are measured by optical measuring sensors at a plurality of measuring points as actual values. The actual values are then compared with predefined reference values and correction values are determined. The installation device is respectively moved by the correction values until the actual values coincide with the reference values. The body part is finally fixed to the body.
WO 2007/003375 A1 discloses a method for joining a first joining structure and a second joining structure, in which an accurately contoured model of the first joining structure and the second joining structure are positioned in relation to each other in a joining position. The model and the second joining structure are measured relative to each other for fitting accuracy in the joining position. Depending on the measurement, a connecting device for the accurately fitting connection of the joining structures is produced on or fixed to the second joining structure.
DE 10 2006 048030 A1 describes a method for determining at least one gap dimension assigned to two contours, in which a three-dimensional image of a region with the gap to be examined is produced. Measured values of contours determining the gap are then smoothed. Starting from a first measuring point on one of the smoothed contours, at a measuring point for which the gap dimension is to be determined, a second measuring point on the respective other smoothed contour is determined in accordance with a stored instruction. The gap dimension sought is determined between the two measuring points. In order to produce the three-dimensional image, a projector projects encoded light onto a region to be imaged. A camera records this region in a color or gray value image, from which a topographic image is generated with the aid of triangulation.
EP 2 423 639 B1 discloses a method for determining gap dimension or flushness of body parts of a motor vehicle, in which body parts to be aligned in relation to one another are scanned three-dimensionally in a multiplicity of predefinable measuring areas, each via a scanning device. Here, a 3-D surface profile of the body parts is measured as objects to be measured. The measuring areas are configured so as to be vehicle-specific. The scanning devices are aligned with at least one body joint by using a predefined vehicle-specific configuration. From scanning values acquired via the scanning devices, three-dimensional surface elements to be assigned to the body parts to be aligned are determined within the measuring areas. Here, three-dimensional surface elements assigned to the body parts to be aligned within the measuring areas are identified from scanned values acquired via the scanning devices. For each of the three-dimensional surface elements determined, position and orientation in space are determined. From type, position and orientation of at least two adjacent three-dimensional surface elements, gap dimension and flushness for at least two body parts to be aligned with each other are determined.